Answer Happy

A random sample of truck speeds for 15 randomly selected trucks traveling on Route 95 in New Rochelle was taken. These are the results (in miles per hour): 57.3, 65.5, 51.3, 66.1, 74.8, 68.9, 63.9, 62.4, 56.4, 57.9, 55.2, 57.2, 59.9, 66.9, 58.4 Truck speeds on Route 95 are known to be normally distributed with an unknown mean of μ and an unknown standard deviation o. (in miles per hour) a) Calculate the sample mean for this data. b) Calculate the sample standard deviation for this data. c) Calculate the maximum likelihood estimate for ² using this data. d) Calculate an unbiased estimate for ² using this data. e) Calculate the sample median for this data. f) Suppose W has a t distribution with 14 degrees of freedom. If P(W> t) = .09 then what is t? g) Suppose W has a t distribution with 14 degrees of freedom. If P(W<t) = .09 then what is t? h) Calculate the 91st percentile of a standard normal distribution. i) Compute an 82% confidence interval for using your answers above. j) Compute an 82% prediction interval for using your answers above. k) Copy your R script or other comments for the above into the text box here.